So using something like Little Snitch is essential. Unfortunately, the only way to recover once you get flagged may be a full uninstall/reinstall as I mention in my post. I've been there. It's a real pita to have to go to all that trouble and backup/preserve all your settings, etc., but it may be the only option.
LaunchBar
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LaunchBar is a smart and powerful productivity utility that provides lightning fast access to applications, documents, contacts and bookmarks, to your iTunes Library, to search engines and more, just by entering short abbreviations of the searched item’s name.
Little Snitch
Little Snitch informs you whenever a program attempts to establish an outgoing Internet connection. You can allow or deny these connections, or define rules to handle future attempts automatically. Little Snitch reliably prevents your private data from being sent out to the Internet without your knowledge.
Micro Snitch
Micro Snitch is an ultra-light menu bar application that operates inconspicuously in the background. It monitors and reports any microphone and camera activity to help you figure out if someone’s spying on you.
Internet Access Policy Viewer
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Internet Access Policy Viewer shows you which of your applications are already equipped with an Internet Access Policy. You can use it to find out where on the Internet your apps connect to and for what purpose they do so.
More Products
Starting with macOS 10.15.4 the above “Legacy System Extension” message will be shown when Little Snitch is installed.
→ Please read this blog post to learn more about why this message is shown.
Will there be an update of Little Snitch that’s compatible with macOS 10.16?
Yes. We are going to release Little Snitch 5 later this year, which will be compatible with macOS 10.16. → Learn more…
Will I get the update for free?
Yes. All licenses sold now include a free upgrade to Little Snitch 5. In addition, customers who purchased Little Snitch 4 within a one-year period prior to the final release of Little Snitch 5 will also get a free upgrade. → Learn more…
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Will Little Snitch 4 run on macOS 10.16?
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Little Snitch 4 will not be loaded on macOS 10.16 by default, but there will still be an option to allow the loading. → Learn more…